Red tides have been sighted in Hong Kong waters over the past week, an inter-departmental red tide working group reported today (April 5).
Agriculture, Fisheries and Conservation Department (AFCD) staff observed a red tide at Tung Ping Chau Marine Park on March 30. Another red tide was spotted by Leisure and Cultural Services Department (LCSD) staff at Silver Mine Bay Beach in Lantau today. A red flag was hoisted immediately. Both red tides still persist.
LCSD staff reported red tide occurrences at Deep Water Bay Beach, Repulse Bay Beach, Middle Bay Beach, South Bay Beach, Shek O Beach and Lo So Shing Beach on Lamma Island on April 3. All the red tides dissipated yesterday.
No associated death of fish has been reported by mariculturists so far.
"The red tides at Tung Ping Chau Marine Park, Deep Water Bay Beach, Repulse Bay Beach, Middle Bay Beach, South Bay Beach, Shek O Beach and Lo So Shing Beach were formed by Noctiluca scintillans, which is common in Hong Kong waters. The one at Silver Mine Bay Beach was formed by Akashiwo sanguinea, which seldom blooms in Hong Kong waters. Both species are non-toxic," a spokesman for the working group said.
The AFCD urged mariculturists at Sha Tau Kok, Ap Chau, Kat O, O Pui Tong, Sai Lau Kong, Tap Mun, Kau Lau Wan, Sham Wan, Sok Kwu Wan, Lo Tik Wan, Po Toi, Ma Wan and Cheung Sha Wan to monitor the situation closely.
Red tide is a natural phenomenon. The AFCD's proactive phytoplankton monitoring programme will continue monitoring red tide occurrences to minimise the impact on the mariculture industry and the public.